PSA: Leaving Dominion is just like leaving any other game type.
Dominion is a teamfight-centered game mode. If you leave, your teammates are even more screwed then they are on SR because the 4v4 windmill fight turns into a 3v4 fight. The only consolation is that they're screwed for less time, since they'll quickly be 5-pointed and lose.
Rules are the same for all maps. If there's any doubt that you won't have time to play, don't queue up.
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